Power boom hoist mechanism for



Dec. 23, 1941. c. F. BALL EI'AL 2,267,691

POWER BOOM HOIS'I MECHANISM FOR-CONCRETE MIXERS Original Filed.June 26, 1939 5 Sheets-Sheet 1 Dec. 23,1941. 0. F. BALL EI'AL POWER BOOM HOIST MECHANISM FOR CONCRETE MIXERS 3 ShetsSheet 2 Original Filed June 26, 1959 Inventors CharlesEfial/l and, I Louis GCHil/cemeer;

Dec. 23, 1941. c. F. BALL ET AL POWER BOOM HOIST MECHANISM FOR CONCRETE MIXERS Original Filed June 26, 1939 3 Sheets-Sheet 5 MNQ Patented Dec. 23, 1941 POWER BOOM HOIST MECHANISM FOR CONCRETE MIXERS Charles F. Ball, Wauwatosa, and Louis G. Hilkemeier, Milwaukee, Wis., assignors to Chain Belt Company, Milwaukee, Wis., a corporation of Wisconsin Original application June 26, 1939, Serial No.

281,299. Divided and this application February 12, 1940, Serial No. 318,594

1 Claim.

This application constitutes a division of our prior co-pending application filed June 26, 1939, Serial No. 281,299 entitled Boom and bucket distributing apparatus for concrete mixers, and the invention herein claimed relates more particularly to the improved mechanism for the raising and lowering of the boom, as illustrated and described in said prior application.

As set forth in the latter, it is now almost universal practice to equip concrete mixers of the paving type with mechanism for distributing the mixed concrete discharged from the mixing drum over areas of considerable extent. Such mechanism commonly comprises a horizontally disposed boom of from twenty to thirty five feet or more in length, having one end pivotally mounted adjacent the discharge opening of the mixing drum for both horizontal and vertical swinging movements, and a receptacle or bucket mounted on such boom for reciprocating travel from and to said discharge opening. The bucket, which may hold a complete batch of a cubic yard or more of mixed concrete, is usually reciprocated on the boom at the will of the operator by means of cables which are power driven in various ways from the engine or motor which drives the mixing drum.

The outer end of the boom is supported by a block and tackle extending from the boom tothe main frame of the mixer, by means of which the boom may be raised and lowered in a vertical plane about its horizontal pivot. Since ordinarily the boom is adjusted vertically at only infrequent intervals, it has heretofore been customary to operate the block and tackle mechanism manually. On the other hand, the boom is swung horizontally quite frequently in a normal concrete pavement placement operation, and such movements are usually accomplished through a manually controlled power drive, such for example as that disclosed in our co-pending application filed June 26, 1939, Serial No. 281,298, entitled Boom swing mechanism for concrete mixers.

While as above indicated the position of the boom in the vertical plane is not changed very often, at the same time the weight of the parts, especially in the case of the larger machines now being built, makes it desirable that the boom elevating and lowering devices be actuated by power rather than by hand. The boom swing mechanism of application No. 281,298 together with the bucket traversing mechanism of application No. 281,299 provide power operating devices on a mixer in a particularly favorable location to deliver power to the boom hoisting and lowering mechanism, and the present invention therefore comprises the provision of means whereby the said raising and lowering mechanism for the boom may be actuated by power at the volition of the operator through a connection to the drive mechanism for the bucket cables.

With the above and other objects in view which will appear as the description proceeds, the invention consists in the novel details of construction and in the novel combinations and arrangements of parts more fully hereinafter disclosed and particularly pointed out in the appended claim.

Referring to the accompanying drawings forming a part of this specification, in which like reference characters designate like parts in all the Views:

Figure 1 is a side elevational view, partly broken away, of the discharge end of a paving concrete mixer having a boom and bucket distributing apparatus, the boom being equipped with raising and lowering mechanism arranged to be power driven from the bucket traversing mechanism disclosed in said parent application No. 281,299;

Fig. 2 is an enlarged sectional elevational view of the bucket traversing and boom hoisting devices, as seen from the left of Fig. 1; and

Fig. 3 is a horizontal sectional view, taken approximately on the plane indicated by the line 3--3 of Fig. 2, showing the spool for the boom raising and lowering cable, the drive mechanism therefor, and the double clutch for selectively connecting the drive to either the bucket cable winding drum or to the boom cable spool.

Referring more particularly to Fig. 1 of the drawings, there is shown the discharge end of a typical paving mixer which may comprise a frame having the horizontal members l5, l6, vertical members I! and a transverse member [8. The said frame is mounted upon crawler treads l9 and has the mixing drum 20 mounted within it upon suitable supporting rollers 2|. The said drum is provided with the usual axial discharge opening 22, see Fig. 2, which may be surrounded by a drip ring 23, through which the mixed concrete is discharged by means of suitable discharge chute members 24 into a distributing bucket 25. This bucket is mounted for reciprocating movements upon a boom 26 by means of a carriage or trolley 21 and is adapted to be moved inwardly and outwardly along the boom by the out-drive cable 28 and the in-drive cable 29, all as may be readily understood by those skilled in the art.

is mounted upon the tubular shaft 9 3 for longi tudinal movements thereon, and its outer periphery is provided with a helical groove I92 for the reception of the out-drive cable 28 and the indrive cable 29, which cables are wound upon the said drum in opposite directions as is common in I the art. For the purpose of maintaining the en- The raising and lowering movements of the boom 26 about its pivot 30 are accomplished by a block and tackle mechanism which includes the elevating and lowering cable 34 and the bucket traverse inwardly and outwardly on the boom is accomplished through the mechanism constituting the subject matter of parent application Serial No. 281,299, which is generally indicated at 35. As fully set forth in our said co-pending application Serial No. 281,298, power for accomplishing the horizontal swinging movements of the boom through the mechanism 33 is derived from the main power plant of the mixer through a drive from the mixing drum 29 which comprises a ring gear or sprocket 36, chain 31 engaging therewith and a sprocket 38 carried by the drive shaft 39 of the boom swinging mechanism 33. As is also fully disclosed in our said co-pending application, the boom swinging mechanism 33 includes a pair of oppositely driven sprockets 49 and 4! which serve as driving means for the bucket operating mechanism and for the boom raising and lowering mechanism constituting the present invention.

Referring now more particularly to Figs. 2 and 3 of the drawings, as is more fully disclosed in said co-pending application Ser. No. 281,299 the bucket traverse mechanism comprises a shaft 45 which is journalled in a bearingbracket 41 rigidly mounted upon the frame members It and I8. The said shaft has spaced sprocket wheels 48 and tering and leaving points of these cables upon the drum in substantial alinement with the fixed sheaves on the frame over which the cables pass to the bucket, the drum is arranged to be moved axially upon the tubular shaft 94 by means of a screw I03 carried by the drum and engaging with a relatively fixed nut I0 1. The said nut carries an upstanding arm I95 which non-rigidly engages a bracket member I 93 mounted on the frame member I3 whereby rotation of the nut is 49 journalled upon it, about which wheels are trained chains 50 and 5| respectively, which chains also engage the sprockets 49 and AI respectively of the boom swinging mechanism 33, whereby the said sprockets 48 and 49 are constantly driven in opposite directions. The sprocket, 48 constitutes the in-drive power transmission and has associated with it a suitable friction clutch 52 arranged to provide a power transmitting connection between the said sprocket and the shaft 45. The sprocket 49 constitutes the out-drive transmission and is arranged to be connected with and disconnected from the shaft 45 by a suitable friction clutch 65. The clutches 52 and 65 are controlled by the shifting levers GI and 13 respectively, which'levers are interconnected by a link 84 so as to move in unison, whereby each clutch may be disengaged and the other sequentially engaged, depending upon the direction in which the levers 6| and I3 are moved, as fully explained in said parent application Serial No. 281,299. The clutch shifting levers GI and '53 are manually movable by the operator through the medium of a bell crank lever 88, one arm of which is connected to the link 94 and the other arm of which is provided with an operating handle 89.

The shaft 65 is connected by a suitable shaft coupling 90 to a shaft 92, see Fig. 3, which shaft 92 is journalled in bearings 93 carried by a tubular shaft 94 surrounding the shaft 92 and journalled in anti-friction bearings 95 mounted in bearing brackets 96 and 91 supported by the frame members I6 and I8. A winding drum 98 prevented, and the said nut is also connected by means of a pair of links IIlI with the fixed bearing bracket 96 which links prevent axial movement of the nut while at the same time permitting limited transverse movement thereof, as does also the non-rigid connection between the arm I and the bracket I96. The nut is thus arranged to accommodate itself to alinement with the shaft 9:3 although rotation and axial movement of the nut are prevented.

A rod I98 is slidably mounted at one end (see Fig. 2) in a depending extension I99 of the bearing bracket 96 and the other end of the said rod is pivotally connected as at Hi) to the clutch operating lever (SI. The rod I98 rigidly carries a pair of adjustable knockout arms III which extend upwardly and embrace the tubular shaft 94, the said arms being so located upon the rod I08 as to be engaged by the hub of the right end plate of the drum 98 or by the end of the screw I93 respectively as the drum 98 approaches the limit of its axial movement in either direction. Upon such contact the drum will move the engaged arm III together with the rod I92 in whichever direction the drum happens to be traveling, and the arrangement is such that this movement of the rod I08 communicatedto the clutch operating levers 6| and 13 will disengage the clutch which at that time is engaged and transmitting power to the drum, whereby rotational and axial movement of the drum will be stopped and overrunning thereof prevented.

As best shown in Figs. 2 and 3, the winding spool I I2 for the boom raising and lowering cable 34 is mounted upon a shaft H3 journalled in a bracket and housing II 'i secured to a frame member I8. Said shaft H3 carries a worm wheel I I5 which is engaged by an irreversible worm I I8 carried by a shaft I I l which is in axial alinement with the shafts 9'2 and 94. The tubular shaft 94 has keyed to its left hand end, as viewed in Figs. 2 and 3, a clutch member Iit which is arranged for engagement with companion clutch elements formed on the right hand face of a shiftable clutch member I29 which is splined upon the shaft 92. The left hand face of the said member I 29 is also provided with clutch elements arranged for engagement with companion elements carried by a clutch member H9, which may be journaled upon the end of shaft 92, and which may also constitute one element of a flexible coupling, the other element I25 of which is keyed on the shaft Ill. The shiftable clutch member I28 is arranged to be moved axially upon the shaft 92 by a shifting yoke I2I, which in turn is actuated by a lever I22 and a link connection I23 from a hand lever I24 located at the opposite side of the machine adjacent the operators station. As here shown these clutches may be of the jaw typeand when in the position shown in Fig. 3 the shaft 92 will not be transmitting power to either the shaft 94 or to the shaft 1, but the normal position is of course such that the driving clutch member I20 is in engagement with the driven clutch member H8 on the shaft 94 so that the latter shaft may drive the winding drum 93 as above described. However, when it becomes necessary or desirable to elevate or lower the boom 26 the clutch member I20 will be shifted through its mechanism I2I, I22, I23 and I24 to disengage the driven clutch member H3 and to engage the member II9, whereupon the shaft 92 will transmit power to the shaft II'I, worm IIS, worm wheel I I5, spool shaft I I3 and spool I I2, whereby the boom elevating and lowering cable 34 will be wound upon or unwound from the spool II2 to raise or lower the boom 26, as will be readily understood.

As above indicated, the boom is only raised or lowered infrequently and normally the clutch member I20 will be out of engagement with the clutch member H9 and in engagement with the clutch member I I8.

While one form of the invention has been illustrated and described it is obvious that those skilled in the art may vary the details of construction as well as the precise arrangement of parts without departing from the spirit of the invention and therefore it is not wished to be limited to the above disclosure except as may be required by the claim.

What is claimed is:

In concrete mixing apparatus provided with distributing mechanism for the mixed concrete comprising a boom pivoted for substantially vertical swinging movements, a bucket mounted thereon, means including a clutch element for causing inward and outward traverse of said bucket upon the boom, and reversible power driven means including a shaft associated with said bucket traverse means, the combination of means including a clutch element for raising and lowering said boom vertically about its pivot; and a clutch element carried by said shaft for alternative engagement with the clutch elements of said boom raising and lowering means and of said bucket traverse means.

CHARLES F. BALL. LOUIS G. HILKEMEIER. 

